1. Field of the Invention
The present disclosure relates to a motor starter having a communication module, and more particularly, to a motor starter capable of monitoring and controlling an magnetic contactor provided in the motor starter from an monitoring console.
2. Description of the Conventional Art
Motor starter is a device including a manual motor starter (hereinafter, abbreviated as a “MMS”) and a magnetic contactor (hereinafter, abbreviated as a “MC”).
As a device used for electrical lines for which the rated voltage is under alternating current 690 V (frequency 50 or 60 Hz) or direct current 250 V, the MMS is an electric device provided at a front connection point of the motor to run or stop the motor. Furthermore, the MMS functions to open an electric power circuit connected to the motor when a fault current such as an over current, phase deficiency, an instant large current, or short circuit current occurs, thereby providing a function capable of protecting the motor from the fault current.
As well known, the MC is a device configured to open or close contacts by magnetizing or demagnetizing the electromagnet using a control signal, thereby supplying electric power to a load device such as a motor to operate the load device to run position or terminating power supply to operate the load device to stop position.
On the other hand, an example of a motor control system including a motor starter according to the related art will be described below with reference to FIG. 1.
A motor control system according to an example of the related art may include a programmable logic controller 10 (hereinafter, abbreviated as “PLC”) for controlling control objects such as magnetic contactors, valves, fans, and the like, an input/output (hereinafter, abbreviated as “I/O”) terminal unit 20 corresponding to an input/output terminal unit of the PLC 10, a terminal unit for connection 30 that provides a unit for signal-connecting the I/O terminal unit 20 with a plurality of motor starters 40, and the plurality of motor starters 40.
In a motor control system having the foregoing configuration according to an example of the related art, in order to run or stop a motor, the MC of the motor starter 40 corresponding to a power supply switch connected to the motor should be controlled by turning it on or off. Accordingly, in order to control the MC of the motor starter 40 to be turned on or off, the PLC 10 controls the MC of the motor starter 40 through the I/O terminal unit 20 and terminal unit for connection 30. In other words, the PLC 10, I/O terminal unit 20, and terminal unit for connection 30 are required to control the MC. Furthermore, in order to control the on/off of the MC, a status signal of the MC should be periodically received by the PLC 10, and an auxiliary relay connected to the MC through the I/O terminal unit 20 and terminal unit for connection 30 is controlled by the PLC 10 based on the status signal to control the on/off of the MC.
Accordingly, when a fault occurs in the PLC 10, the status of the MC is unable to be monitored and the on/off control of the MC is disabled, thereby having the possibility of causing a great damage on the motor and a facility driven by the motor.
Moreover, according to a motor control system in the related art, when an additional motor starter 40 is further installed for an additional function, the addition of the auxiliary relay, I/O terminal unit 20 and terminal unit for connection 30 may be necessary as well as an additional wiring work may be required, thereby causing an increase of the cost and an increase of the occupied space.